A glomerular disease (primary glomerular nephritis) brought about by causing lesion in a glomerulus of a kidney is clinically classified into any of seven diseases consisting of acute nephritis after infected with hemolytic streptococcus, crescentic glomerulonephritis (rapidly progressive nephritis), IgA nephropathy, membranous nephropathy, membranous proliferative nephropathy, focal glomerulonephritis and minimal change nephrotic syndrome. Among them, the diseases other than the acute nephritis after infected with hemolytic streptococcus, the crescentic glomerulonephritis and the minimal change nephrotic syndrome are generally called chronic glomerular nephritis, and the cause and the time of onset thereof are relatively indistinct in many cases. Further, the lesion processes thereof is mostly progressive and results in renal failure in many cases.
Medicines which fundamentally heal such glomerular diseases have not yet been found, and agents such as a steroid agent, an anti-thrombocytic agent, an anticoagulant agent and an immunosuppersive agent are used for the purpose of inhibiting or retarding transition to dialysis by drug therapy.
Among them, the anti-thrombocytic agent has a function to inhibit discharge of various mediators such as thromboxane A2, histamine, a leukocyte migrating factor, cytokine and a proliferative factor from a blood platelet, and therefore it is considered that use of the present agent makes it possible to inhibit progressive augmentation of a glomerular disease caused by proliferation of a mesangium cell and a failure in a barrier mechanism in a glomerular snare wall which are brought about by various mediators (Cameron J S et al.: Coagulation and thromboembolic complications in the nephrotic syndrome. Adv Nephrol 13:75, 1984).
Further, it is reported that in a kidney disease, the degree of hyperlipidemia statistically correlates with the degree of proteinuria deterioration or aggravation in renal function, and a hyperlipidemia therapeutic agent such as an HMG-CoA reductase inhibitor is used as well for therapy of a kidney disease for the purpose of removing an augmentative factor of a kidney disease of hyperlipidemia.
However, a kidney disease-improving effect brought about when using an anti-thrombocytic agent and a hyperlipidemia therapeutic agent is limited, and still remains unsatisfactory.
An object of the present invention is to provide a drug exhibiting an excellent effect in prevention or therapy of a glomerular disease.